1. Technical Field
The present invention relates to a polarizer unit and a projector including the polarizer unit.
2. Related Art
There is a known projector in which light outputted from a light source apparatus is modulated by a light modulator in accordance with image information and the modulated light is projected through a projector lens onto a projection surface. In such a projector, reduction in size and increase in luminance advance year after year.
When a transmissive liquid crystal panel is used as the light modulator, in positions upstream (on light incident side) and downstream (on light exiting side) of the liquid crystal panel are provided polarizers (light-incident-side polarizer and light-exiting-side polarizer). As the luminance of the projector increases, the polarizers are likely to deform due to heat generated by the light from the light source apparatus. To prevent the deformation due to the heat, an organic polarizer has been replaced with an inorganic polarizer.
JP-A-2010-128225 discloses a polarizing glass plate unit in which a polarizing glass plate formed only of a reduction layer with no glass layer is bonded to a light transmissive substrate having thermal conductivity higher than that of the glass substrate with an inorganic adhesive and further discloses that the polarizing glass plate unit is used to increase cooling performance.
In JP-A-2010-128225, however, it is necessary to bond the polarizing glass plate (structure in which polarizing layer is provided in optical base) to the light transmissive substrate with an inorganic adhesive. The bonding process requires management of the amount of the adhesive, undesirably resulting in an increase in man-hours. When the polarizing glass plate is replaced with a wire-grid polarizer (structure in which polarizing layer is provided on surface of optical substrate) and the technology disclosed in JP-A-2010-128225 is applied, the adhesive is likely to spill over the substrate surface on which the wire-grid layer is formed and undesirably penetrate through or otherwise damage the polarizing layer, resulting in a concern about a serious adverse effect on the optical characteristics of the polarizing glass unit.
It is therefore desired to provide a polarizer unit that is readily assembled and has improved cooling performance and a projector including the polarizer unit.